Oh, please, don't cook a pork loin to that temp. It will be dry, very very done and almost inedible. Cook it to 145 or at most 150* and let it rest. It will be rosy and juicy and pretty good. They are just so lean now. I have all but given up on roasting, and just use braising recipes which are delicious.

As with most meats, pork loin is usually cooked by so many minutes to the pound. I believe that it's cooked to an internal temp of abut 165 degrees.

Not too much higher than that, or it will start to dry out and become tough.

I'm of the school, pork tenderloin or pork roast, needs to be cooked at a high heat and quickly. Sear in juices then bake at a fairly high temperature for a short amount of time. Use your thermometer to check for doneness.